Mon·Nov 27, 2023Monday·November 27, 2023

1. 01*

   Quark-photon vertex in confining models

   C. Mena🇧🇷 · L. F. Palhares (Rio de Janeiro State University)🇧🇷

   We compute the one-loop quark-photon vertex and the quark magnetic moment in three different models with an infrared-modified gluon propagator, namely: the massive (Curci-Ferrari-like) model, the Gribov-Zwanziger model, and the Refined Gribov-Zwanziger model. We show results for the $F_2$ form factor and analyze the role played by the mass parameters associated with the confined gluon in these models. Using the framework of the Constituent Quark Model, we further construct the observable proton magnetic moment including the effects of QCD interactions generated by the different confining models. Our results show that there is no qualitative observable difference stemming from the presence of complex-conjugated poles. On the other hand, quantitative differences between the various confining models can be sizable, so that observable constraints would in principle be possible, provided one has sufficient information about the constituent quark mass and the QCD running coupling.

   hep-phhep-thnucl-th4 citations
2. 02*

   Gravitational Dark Matter from Minimal Preheating

   Ruopeng Zhang🇨🇳 · Sibo Zheng🇨🇳

   Following our previous work, we continue to explore gravitational dark matter production during the minimal preheating caused by inflaton self-resonance. In this situation there is only one dimensionless index parameter $n$ characterizing the inflation potential after the end of inflation, which leads to a robust prediction on the gravitational dark matter relic abundance. Using lattice method to handle the non-perturbative evolutions of relevant quantities during the inflaton self-resonance, we derive the gravitational dark matter relic abundance arising from both the inflaton condensate and fluctuation annihilation. While being absent for $n=2$, the former one can instead dominate over the later one for $n=4,6$. Our results show that gravitational dark matter mass of $1.04(2.66)\times 10^{14}$ GeV accommodates the observed value of dark matter relic abundance for $n=4$ (6).

   hep-phastro-ph.COJHEP(2024)·18 citations
3. 03*

   Light Shining Through Wall Bounds on Axions From Obscured Magnetars

   Dibya S. Chattopadhyay🇮🇳 · Basudeb Dasgupta🇮🇳 · Amol Dighe🇮🇳 · Mayank Narang🇮🇳

   Coupling of axions or axion-like particles (ALPs) with photons may lead to photons escaping optically opaque regions by oscillating into ALPs. This phenomenon may be viewed as the Light Shining through Wall (LSW) scenario. While this LSW technique has been used previously in controlled laboratory settings to constrain the ALP-photon coupling ($g_{a\gamma }$), we show that this can also be applied in astrophysical environments. We find that obscured magnetars in particular are excellent candidates for this purpose. A fraction of photons emitted by the magnetar may convert to ALPs in the magnetar neighborhood, cross the large absorption column densities, and convert back into photons due to the interstellar magnetic field. Comparing the observed flux with the estimated intrinsic flux from the magnetar, we can constrain the contribution of this process, and hence constrain $g_{a\gamma }$. The effects of resonant conversion near the magnetar as well as ALP-photon oscillations in the interstellar medium are carefully considered. Taking a suitable magnetar candidate PSR J1622-4950, we find that the ALP-photon coupling can be constrained at $g_{a\gamma }\lesssim (10^{-10}-10^{-11})$ GeV${}^{-1}$ for low mass axions ($m_a\lesssim 10^{-12}$ eV). Our study reveals the previously unrealized potential for employing the LSW technique for obscured magnetars for probing and constraining ALP-photon couplings.

   hep-phastro-ph.HEJCAP(2026)·5 citations
4. 04*

   Roberge-Weiss periodicity and singularity in hadron resonance gas model with excluded volume effects

   Riki Oshima🇯🇵 · Hiroaki Kouno🇯🇵 · Kouji Kashiwa🇯🇵

   Quantum chromodynamics (QCD) with pure imaginary baryon number chemical potential mu =i theta T, where T is temperature and theta is a real number, has the Roberge-Weiss periodicity. We study the theta-dependence of the baryon number density and the pressure in the hadron resonance gas model with excluded volume effects of baryons. It is shown that the baryon number density and the pressure are smooth periodic functions of theta at low or high temperature. However, they have singular behavior at theta =(2k+1)pi where k is an integer, when T sim 211MeV. This temperature is consistent with the Roberge-Weiss transition temperature TRW obtained by lattice QCD simulations. This singularity can be explained by the dual excluded volume effects in which the roles of point-like and non point-like particles are exchanged each other in the ordinary excluded volume effects. It is also indicated that the excluded volume effect is visible just below TRW and is directly detectable by the lattice QCD simulation at finite theta. We compare the results with the one obtained by the Polyakov-loop extended Nambu-Jona-Lasinio model.

   hep-phhep-latnucl-thPRD(2025)·4 citations
5. 05*

   Meson production in $J/\psi$ decays and $J/\psi \to N\bar{N}\gamma$ process

   S.G. Salnikov🇷🇺 · A.I. Milstein🇷🇺

   It is shown that an account for the final-state interaction of real or virtual nucleon and antinucleon produced in the processes $J/\psi \to p\bar{p}\gamma$, $\psi (2S)\to p\bar{p}\gamma$, $J/\psi \to p\bar{p}\omega$, and $J/\psi \to 3\left({\pi }^{+}{\pi }^{-}\right)\gamma$ near the threshold of $N\bar{N}$ pair production allows one to obtain self-consistent description of these processes. Predictions of our model are in good agreement with experimental data available. The proposed potential model also reproduces the corresponding partial cross sections of $p\bar{p}$ scattering.

   hep-phhep-exNPB(2024)·8 citations
6. 06*

   Correction to Bjorken Energy Density Calculations for Central A-A Collisions

   O.M. Shaposhnikova🇷🇺 · A.A. Marova🇷🇺 · G.A. Feofilov🇷🇺

   We present geometry-based corrections to estimates of the Bjorken energy density in a broad range of heavy-ion collision energies (from RHIC to the LHC) considereing non-circular shape of the nuclei overlap area in case of events selected in 0-5% centrality classes. We compare the updated Bjorken energy excitation function, obtained in our study for these very central A-A collisions, to the previously obtained ones. We present also and discuss the relevant energy dependences of pion, kaon and proton contributions to the Bjorken energy density that are also estimated in our study.

   hep-phPhys.Atom.Nucl.(2023)·1 citation
7. 07*

   Contrasting observables related to the $N^{\ast }(1535)$ from the molecular or a genuine structure

   Hai-Peng Li🇨🇳 · Jing Song🇨🇳 · Wei-Hong Liang🇨🇳 · R. Molina🇪🇸 · E. Oset🇪🇸

   In this work we compare the predictions for the scattering length and effective range of the channels $K^0{\Sigma }^{+},K^{+}{\Sigma }^0,K^{+}\Lambda$ and $\eta p$, assuming the $N^{\ast }(1535)$ state as a molecular state of these channels, or an original genuine state, made for instance from three quarks. Looking at very different scenarios, what we conclude is that the predictions of these two pictures are drastically different, to the point that we advise the measurement of these magnitudes, accessible for instance by measuring correlation functions, in order to gain much valuable information concerning the nature of this state.

   hep-phnucl-thEPJC(2024)·17 citations
8. 08*

   Derivation of the Cross-Free Family representation for the box diagram

   Zeno Capatti🇨🇭

   I work out in full detail the derivation of the Cross-Free Family (CFF) representation for the box diagram, and highlight the differences with its Time Ordered Perturbation Theory (TOPT) representation. I briefly discuss implications for the threshold singularity structure of the diagram.

   hep-phhep-thPoS(2024)·8 citations
9. 09*

   Precision Top Mass Measurement Using Energy Correlators

   Jack Holguin🇬🇧 · Ian Moult🇺🇸 · Aditya Pathak🇩🇪 · Massimiliano Procura🇦🇹 · Robert Schöfbeck · Dennis Schwarz🇦🇹

   Precision top mass measurements at hadron colliders have been notoriously difficult. The fundamental challenge in the current approaches lies in achieving simultaneously high top mass sensitivity and good theoretical control. Inspired by the use of standard candles in cosmology, we overcome this problem by showing that a single energy correlator-based observable can be constructed that reflects the characteristic angular scales associated with both the $W$-boson and top quark. This gives direct access to the dimensionless quantity $m_t/m_W$, from which $m_t$ can be extracted in a well-defined short-distance mass scheme as a function of the well-known $m_W$. A Monte-Carlo-based study is performed to demonstrate the properties of our observable and the statistical feasibility of its extraction from the Run 2 and 3 and High-Luminosity LHC data sets. The resulting $m_t$ has remarkably small uncertainties from hadronization effects and is insensitive to the underlying event and parton distribution functions. Our proposed observable provides a road map for a rich program to achieve a top mass determination at the LHC with record precision.

   hep-phhep-exPoS(2024)·3 citations
10. 10*

    Isospin Decomposition of D Mesons

    Shakeel Mahmood🇵🇰 · Mudassir Hussain🇵🇰 · Abrar Ahmad🇵🇰

    This work focuses on decomposition of isospin amplitude of D meson non-leptonic decays. Isospin vector algebra is used to show the equivalency of two amplitude decompositions. We restrict to the transitions involving only Del I = 1 and Del I = 0: The isospin symmetry is relating charge channel (D+ -> K+,Pi+ Pi-; D+ -> K+, Pi0, Pi0 and D+-> K0, Pi0,Pi+); and neutral channel (D0 -> K0,Pi+,Pi- D0 -> K0, Pi0, Pi0 and D0 -> K+, Pi0, Pi-) with each other. Equivalent triangle relations are obtained for both channels.

    hep-ph0 citations
11. 11*

    An NJL model analysis of a magnetised nonextensive QCD medium

    Chowdhury Aminul Islam🇩🇪

    We investigate the effect of a background magnetic field when applied to a nonextensive QCD medium in a $2+1$ flavour Nambu\textemdash Jona-Lasinio model. The effect of a constant as well as an $eB$-dependent coupling is considered. For the constant coupling, the well-known magnetic catalysis effect is observed with reduced strength in both the condensates and the transition temperatures compared to the standard extensive medium. In the case of a field-dependent coupling, we observe a competition between the nonextensive parameter, $q$ and $eB$. With sufficiently high $q$-values, the phenomenon of inverse magnetic catalysis \textemdash\, a well-known trait in effective models featuring $eB$-dependent coupling, appears to be eliminated within the range of magnetic fields examined in our present study.

    hep-phnucl-thEPJA(2024)·6 citations
12. 12*

    Accessing the gravitational form factors of the nucleon and nuclei through a massive graviton

    Yoshitaka Hatta🇺🇸

    In contrast to the electromagnetic form factors of the nucleon and nuclei that have been extensively studied in electron scattering, there is no known way to directly measure the gravitational form factors (GFFs), the off-forward hadronic matrix element of the QCD energy-momentum tensor. I suggest exploring the possibility to use massive gravitons in beyond the Standard Model and General Relativity scenarios as a means to access the GFFs of the proton and nuclei at future TeV-scale lepton-ion colliders.

    hep-phPRD(2024)·21 citations
13. 13*

    Spin oscillations in neutrino gravitational scattering

    Mridupawan Deka (1)🇷🇺 · Maxim Dvornikov (1 and 2) ((1) JINR, (2) IZMIRAN)🇷🇺

    We study neutrino spin oscillations while the particles scatter off a rotating black hole surrounded by a thick magnetized accretion disk. Neutrino spin precession is caused by the interaction of the neutrino magnetic moment with the magnetic field in the disk which has both toroidal and poloidal components. Our calculation of the observed neutrino fluxes, accounting for spin oscillations, are based on numerical simulations of the propagation of a great number of incoming test particles using High Performance Parallel Computing. The obtained results significantly improve our previous findings. We briefly discuss the applications for the observations of astrophysical neutrinos.

    hep-phastro-ph.HEgr-qcPhys.Atom.Nucl.(2024)·4 citations
14. 14*

    Is there a (Pseudo)Scalar at 95 GeV?

    Giorgio Arcadi🇮🇹 · Giorgio Busoni🇦🇺 · David Cabo-Almeida🇮🇹 · Navneet Krishnan🇦🇺

    We discuss the possibility of interpreting the recent experimental hints, in favour of a 95 GeV resonance, with extensions of the Standard Model featuring an extra Higgs doublet and SM scalar (2HDM+s) or pseudoscalar singlet (2HDM+a). The possibility of reproducing the experimental anomalies will be compared with the theoretical constraints on the extended Higgs sector as well as complementary bounds coming from flavour physics as well as other colliders searchers. For both the 2HDM+s and 2HDM+a we will consider a generic natural flavour conserving (NFC) as well as the customary Type-I, -II, -X and -Y configurations of the Yukawa coupling to the BSM Higgs bosons.

    hep-phPRD(2024)·34 citations
15. 15*

    Common femtoscopic hadron-emission source in pp collisions at the LHC

    ALICE Collaboration

    The femtoscopic study of pairs of identical pions is particularly suited to investigate the effective source function of particle emission, due to the resulting Bose-Einstein correlation signal. In small collision systems at the LHC, pp in particular, the majority of the pions are produced in resonance decays, which significantly affect the profile and size of the source. In this work, we explicitly model this effect in order to extract the primordial source in pp collisions at $\sqrt{s}=13$ TeV from charged $\pi -\pi$ correlations measured by ALICE. We demonstrate that the assumption of a Gaussian primordial source is compatible with the data and that the effective source, resulting from modifications due to resonances, is approximately exponential, as found in previous measurements at the LHC. The universality of hadron emission in pp collisions is further investigated by applying the same methodology to characterize the primordial source of K$-$p pairs. The size of the primordial source is evaluated as a function of the transverse mass ($m_{\mathrm{T}}$) of the pairs, leading to the observation of a common scaling for both $\pi -\pi$ and K$-$p, suggesting a collective effect. Further, the present results are compatible with the $m_{\mathrm{T}}$ scaling of the p$-$p and p$-\Lambda$ primordial source measured by ALICE in high multiplicity pp collisions, providing additional evidence for the presence of a common emission source for all hadrons in small collision systems at the LHC. This will allow the determination of the source function for any hadron-hadron pairs with high precision, granting access to the properties of the possible final-state interaction among pairs of less abundantly produced hadrons, such as strange or charmed particles.

    hep-phhep-exnucl-exEPJC(2025)·44 citations
16. 16*

    Constraints on metastable superheavy dark matter coupled to sterile neutrinos with the Pierre Auger Observatory

    The Pierre Auger Collaboration: A. Abdul Halim🇦🇺 · P. Abreu🇵🇹 · M. Aglietta🇮🇹 · I. Allekotte🇦🇷 · K. Almeida Cheminant🇵🇱 · A. Almela🇦🇷 · R. Aloisio🇮🇹 · J. Alvarez-Muñiz🇪🇸 · J. Ammerman Yebra🇪🇸 · G.A. Anastasi🇮🇹 · L. Anchordoqui🇺🇸 · B. Andrada🇦🇷 and 358 other authors

    Dark matter particles could be superheavy, provided their lifetime is much longer than the age of the universe. Using the sensitivity of the Pierre Auger Observatory to ultra-high energy neutrinos and photons, we constrain a specific extension of the Standard Model of particle physics that meets the lifetime requirement for a superheavy particle by coupling it to a sector of ultra-light sterile neutrinos. Our results show that, for a typical dark coupling constant of 0.1, the mixing angle ${\theta }_m$ between active and sterile neutrinos must satisfy, roughly, ${\theta }_m\lesssim 1.5\times 10^{-6}(M_X/10^9\mathrm{GeV}{)}^{-2}$ for a mass $M_X$ of the dark-matter particle between $10^8$ and $10^{11}$GeV.

    hep-phastro-ph.HEPRD(2024)·18 citations
17. 17*

    Hadron-Level NLO predictions for QCD Observables in Photo-Production at the Electron-Ion Collider

    Peter Meinzinger🇬🇧 · Frank Krauss🇬🇧

    We present the first next-to leading order accurate hadron-level predictions for inclusive QCD and jet observables in photo-production for the upcoming electron--ion collider.

    hep-phPRD(2024)·10 citations
18. 18*

    Stability of domain walls with inflationary fluctuations under potential bias, and gravitational wave signatures

    Naoya Kitajima🇯🇵 · Junseok Lee🇯🇵 · Fuminobu Takahashi🇯🇵 · Wen Yin🇯🇵

    A recent study has shown that domain walls with inflationary initial fluctuations exhibit remarkable stability against population bias due to long-range correlations, challenging the claims of prior research. In this paper, we study the dynamics of these domain walls in the presence of potential bias and show that they collapse with a lifetime several times longer than that due to thermal fluctuations. This is interpreted as a difference in the average distance between domain walls, leading us to derive a new formula for the domain wall lifetime which depends on the area parameter in a qualitatively different way from previous studies. In addition, we compute the spectrum of gravitational waves generated by such domain walls and find that both the peak frequency and the peak abundance are lowered in a manner that depends on the area parameter. Based on these findings, we also determine the necessary degree of vacuum degeneracy for axion domain walls to explain the isotropic cosmic birefringence.

    hep-phastro-ph.COgr-qcJCAP(2025)·47 citations
19. 19*

    Light New Physics in $B\to K^{(\ast )}\nu \bar{\nu }$?

    Wolfgang Altmannshofer🇺🇸 · Andreas Crivellin🇨🇭 · Huw Haigh🇦🇹 · Gianluca Inguglia🇦🇹 · Jorge Martin Camalich🇪🇸

    The study of the rare decays $B\to K^{(\ast )}\nu \bar{\nu }$ offers a window into the dynamics operating at the electroweak scale, allowing studies of the Standard Model and searches for heavy new physics. However, the analysis of these decays is also potentially sensitive to the on-shell production of new light bosons $X$ through the process $B\to K^{(\ast )}X$. In particular, Belle~II has recently measured $B^{+}\to K^{+}\nu \bar{\nu }$, finding a $2.8\sigma$ excess under the assumption of heavy new physics. Since this excess is rather localized in the kaon energy, a fit that includes the decay mode $B^{+}\to K^{+}X$ to the kinematic distributions prefers $m_X\approx 2$GeV with branching fraction Br$[B\to KX]=(8.8\pm 2.5)\times 10^{-6}$ and a significance of $\approx 3.6\sigma$. However, no excess was found in the BaBar measurements of $B\to K^{(\ast )}\nu \bar{\nu }$, and a global analysis of the Belle II and BaBar data leads to Br$[B\to KX]=(5.1\pm 2.1)\times 10^{-6}$ with a reduced significance of $\approx 2.4\sigma$. We then study various simplified dark-flavoured models and present a possible UV completion based on a gauged $B_3-L_3$ symmetry, highlighting the discovery potential of dedicated searches for $B\to K^{(\ast )}X$ at Belle II.

    hep-phhep-exPRD(2024)·90 citations
20. 20*

    Baryon Asymmetry from the Decay and Scattering of a Majorana Fermion Pair Coupled to Quarks

    Shrihari Gopalakrishna🇮🇳 · Rakesh Tibrewala🇮🇳

    We compute the baryon asymmetry in decay and scattering processes involving the electromagnetically charge-neutral fermion $\chi$ that carries nonzero baryon number and interacts with quark-like fermions $U,D$ via a vector-vector dimension-six effective operator, in the theory we developed in our earlier work. Majorana masses for the $\chi$ break baryon number and split the Dirac fermion $\chi$ into a pair of Majorana fermions $X_n$ with indefinite baryon number. We identify loop amplitudes for $X_n$ decay and scattering processes that are sensitive to the baryon number violation. The phases in the Majorana mass and couplings, in conjunction with the phase from intermediate onshell states, lead to $C$ and $CP$ violation in these processes. For some representative parameter choices, we numerically compute the decay and scattering baryon asymmetries between the process and its conjugate process, and find that the asymmetry generated is very interesting for explaining the baryon asymmetry of the Universe.

    hep-phPRD(2025)·1 citation
21. 21*

    JetLOV: Enhancing Jet Tree Tagging through Neural Network Learning of Optimal LundNet Variables

    Mauricio A. Diaz🇬🇧 · Giorgio Cerro🇬🇧 · Jacan Chaplais🇬🇧 · Srinandan Dasmahapatra🇬🇧 · Stefano Moretti🇬🇧

    Machine learning has played a pivotal role in advancing physics, with deep learning notably contributing to solving complex classification problems such as jet tagging in the field of jet physics. In this experiment, we aim to harness the full potential of neural networks while acknowledging that, at times, we may lose sight of the underlying physics governing these models. Nevertheless, we demonstrate that we can achieve remarkable results obscuring physics knowledge and relying completely on the model's outcome. We introduce JetLOV, a composite comprising two models: a straightforward multilayer perceptron (MLP) and the well-established LundNet. Our study reveals that we can attain comparable jet tagging performance without relying on the pre-computed LundNet variables. Instead, we allow the network to autonomously learn an entirely new set of variables, devoid of a priori knowledge of the underlying physics. These findings hold promise, particularly in addressing the issue of model dependence, which can be mitigated through generalization and training on diverse data sets.

    hep-phcs.LG2 citations
22. 22*

    The QCD vacuum as a disordered chromomagnetic condensate

    Paolo Cea🇮🇹

    An attempt is made to describe from first principles the large-scale structure of the confining vacuum in quantum chromodynamics. Starting from our previous variational studies of the SU(2) pure gauge theory in an external Abelian chromomagnetic field and extending the Feynman's qualitative analysis in (2+1)-dimensional SU(2) gauge theory, we show that the SU(3) vacuum in three-space and one-time dimensions behaves like a disordered chromomagnetic condensate. Color confinement is assured by the presence of a mass gap together with the absence of color long-range correlations. We offer a clear physical picture for the formation of the flux tube between static quark charges that allowed to determine the color structure and the transverse profile of the flux-tube chromoelectric field. The transverse profile of the flux-tube chromoelectric field turns out to be in reasonable agreement with lattice data. We, also, show that our quantum vacuum allows for both the color and ordinary Meissner effect. We find that for massless quarks the quantum vacuum could accommodate a finite non-zero density of fermion zero modes leading to the dynamical breaking of the chiral symmetry.

    hep-phhep-latUniverse(2024)·6 citations
23. 23*

    The Role of Vectors in Reheating

    Marcos A. G. Garcia🇲🇽 · Kunio Kaneta🇯🇵 · Wenqi Ke🇫🇷 · Yann Mambrini🇫🇷 · Keith A. Olive🇺🇸 · Sarunas Verner🇺🇸

    We explore various aspects concerning the role of vector bosons during the reheating process. Generally, reheating occurs during the period of oscillations of the inflaton condensate and the evolution of the radiation bath depends on the inflaton equation of state. For oscillations about a quadratic minimum, the equation of state parameter, $w=p/\rho =0$, and the evolution of the temperature, $T(a)$ with respect to the scale factor is independent of the spin of the inflaton decay products. However, for cases when $w>0$, there is a dependence on the spin, and here we consider the evolution when the inflaton decays or scatters to vector bosons. We also investigate the gravitational production of vector bosons as potential dark matter candidates. Gravitational production predominantly occurs through the longitudinal mode. We compare these results to the gravitational production of scalars.

    hep-phastro-ph.COJCAP(2024)·15 citations
24. 24*

    Pulsar Nulling and Vacuum Radio Emission from Axion Clouds

    Andrea Caputo🇨🇭 · Samuel J. Witte🇬🇧 · Alexander A. Philippov🇺🇸 · Ted Jacobson🇺🇸

    Non-relativistic axions can be efficiently produced in in the polar caps of pulsars, resulting in the formation of a dense cloud of gravitationally bound axions. Here, we investigate the interplay between such an axion cloud and the electrodynamics in the pulsar magnetosphere, focusing specifically on the dynamics in the polar caps, where the impact of the axion cloud is expected to be most pronounced. For sufficiently light axions $m_a\lesssim 10^{-7}$ eV, we show that the axion cloud can occasionally screen the local electric field responsible for particle acceleration and pair production, inducing a periodic nulling of the pulsar's intrinsic radio emission. At larger axion masses, the small-scale fluctuations in the axion field tend to suppress the back-reaction of the axion on the electrodynamics; however, we point out that the incoherent oscillations of the axion in short-lived regions of vacuum near the neutron star surface can produce a narrow radio line, which provides a complementary source of radio emission to the plasma-resonant emission processes identified in previous work. While this work focuses on the leading order correction to pair production in the magnetosphere, we speculate that there can exist dramatic deviations in the electrodynamics of these systems when the axion back-reaction becomes non-linear.

    hep-phastro-ph.COastro-ph.HEPRL(2024)·29 citations
25. 25*

    Scattering from an external field in quantum chromodynamics at high energies: from foundations to interdisciplinary connections

    Athanasia-Konstantina Angelopoulou🇮🇪 · Anh Dung Le🇫🇮 · Stéphane Munier🇫🇷

    We review the factorization of the $S$-matrix elements in the context of particle scattering off an external field, which can serve as a model for the field of a large nucleus. The factorization takes the form of a convolution of light cone wave functions describing the physical incoming and outgoing states in terms of bare partons, and products of Wilson lines. The latter represent the interaction between the bare partons and the external field. Specializing to elastic scattering amplitudes of onia at very high energies, we introduce the color dipole model, which formulates the calculation of the modulus-squared of the wave functions in quantum chromodynamics with the help of a branching random walk, and the scattering amplitudes as observables on this classical stochastic process. Methods developed for general branching processes produce analytical formulas for the asymptotics of such observables, and thus enable one to derive exact large-rapidity expressions for onium-nucleus cross sections, from which electron-nucleus cross sections may be inferred.

    hep-phSciPost Phys.Lect.Notes(2025)·9 citations
26. 26*

    Neutrinos for TeV Neutralinos

    Carsten Rott🇺🇸 · Pearl Sandick🇺🇸 · Ben Sheff🇺🇸

    One of the most well-founded candidates for dark matter remains a split-SUSY model with a Higgsino-like or Wino-like lightest superpartner and the grander SUSY model providing answers for the hierarchy problem and GUT scale unification.The relatively heavy scalar superpartners imply such models would not yet be seen at collider experiments, and mixing-suppressed couplings place such models outside the reach of current direct detection experiments. As such particles annihilate fairly readily to electroweak bosons, a significant neutrino signal can arise near the galactic center that may be visible to dedicated searches at current and future neutrino telescopes.

    hep-phhep-exPRD(2024)·2 citations
27. 27*

    A pion decay constant in the multi-flavor Schwinger model

    Jaime Fabián Nieto Castellanos🇲🇽 · Ivan Hip🇭🇷 · Wolfgang Bietenholz🇲🇽

    The pion decay constant $F_{\pi }$ plays an important role in QCD and in Chiral Perturbation Theory. It is hardly known, however, that a corresponding constant exists in the Schwinger model with $N_{\mathrm{f}}\ge 2$ degenerate fermion flavors. In this case, the ``pion'' does not decay and $F_{\pi }$is dimensionless. Still, $F_{\pi }$ can be defined by 2d analogies to the Gell-Mann--Oakes--Renner relation, the Witten--Veneziano formula and the residual ``pion'' mass in the $\delta$-regime. With suitable assumptions, and by inserting simulation data, these QCD-inspired relations are all compatible with $F_{\pi }\simeq 1/\sqrt{2\pi }$ at zero fermion mass, as we observe for $N_{\mathrm{f}}=2,\dots ,6$. We conclude that this is a meaningful constant in the multi-flavor Schwinger model.

    ↳ hep-lathep-phPoS(2024)·0 citations
28. 28*

    Holographic Fluids from 5D Dilaton Gravity

    Sylvain Fichet🇧🇷 · Eugenio Megias🇪🇸 · Mariano Quiros🇪🇸

    We study a solvable class of five-dimensional dilaton gravity models that continuously interpolate between anti-de Sitter (AdS${}_5$), linear dilaton (LD${}_5$) and positively curved spacetimes as a function of a continuous parameter $\nu$. The dilaton vacuum expectation value is set by a potential localized on a flat brane. We chart the elementary properties of these backgrounds for any admissible $\nu$, and determine stability conditions of the brane-dilaton system. We find that the spectrum of metric fluctuations can be either continuous or discrete. It features a massless graviton mode confined between the brane and the curvature singularity, and a massive radion mode tied to brane-dilaton stability. We show that, in the presence of a bulk black hole, the holographic theory living on the brane features a perfect fluid. The equation of state of the holographic fluid interpolates between radiation, pressureless matter and vacuum energy as a function of $\nu$. This extends earlier findings on holographic fluids. Our results suggest that the thermodynamics of the fluid mirrors precisely the thermodynamics of the bulk black hole.

    ↳ hep-thhep-phJHEP(2024)·14 citations
29. 29*

    Exploring percolation phase transition in the three-dimensional Ising model with machine learning

    Ranran Guo🇨🇳 · Xiaobing Li🇨🇳 · Rui Wang🇨🇳 · Shiyang Chen🇬🇧 · Yuanfang Wu🇨🇳 · Zhiming Li🇨🇳

    The percolation study offers valuable insights into the characteristics of phase transition, shedding light on the underlying mechanisms that govern the formation of global connectivity within the system. We explore the percolation phase transition in the 3D cubic Ising model by employing two machine learning techniques. Our results demonstrate the capability of machine learning methods in distinguishing different phases during the percolation transition. Through the finite-size scaling analysis on the output of the neural networks, the percolation temperature and a correlation length exponent in the geometrical percolation transition are extracted and compared to those in the thermal magnetization phase transition within the 3D Ising model. These findings provide a valuable way essential for enhancing our understanding of the property of the QCD critical point, which belongs to the same universality class as the 3D Ising model.

    ↳ nucl-thhep-phCPC(2025)·1 citation
30. 30*

    Highlights of recent BESIII results

    Vindhyawasini Prasad🇨🇱

    This report highlights the recent BESIII results related to the measurement of the $R$ value, radiative decays of $J/\psi$ and the polarization of $D^0\to \omega \varphi$ decay. BESIII, a symmetric electron-positron collider experiment, has collected a large data sample at several energy points in the tau-charm region, including the $J/\psi$ and $\psi (3770)$ resonances. Based on the data samples collected at 14 center-of-mass energy ($\sqrt{s}$) points between 2.2323 and 3.671 GeV, BESIII has achieved a measurement of the $R$ value with an accuracy down to the level of $2.6\%$ for $\sqrt{s}<3.1$ GeV and $3.0\%$ for $\sqrt{s}>3.1$ GeV. BESIII has also observed the $X(2600)$ resonance in radiative $J/\psi$ decay and the polarization of $D^0\to \omega \varphi$ for the first time. The polarization of $D^0\to \omega \varphi$ saturates with completely transverse polarization, which is inconsistent with the existing theoretical models. These results are useful in testing the predictions of the Standard Model.

    ↳ hep-exhep-phInt.J.Mod.Phys.A(2024)·3 citations
31. 31*

    Monte Carlo Simulation Development and Implementation of the GiBUU Model for Neutrino Experiments

    Leonidas Aliaga Soplin🇺🇸 · Raquel Castillo Fernandez🇺🇸 · Jasper Gustafson🇺🇸 · Declan Quinn🇺🇸 · Shweta Yadav🇺🇸

    This paper introduces a Monte Carlo simulation generated with the GiBUU model for neutrino experiments. The simulation generates realistic neutrino event samples, contributing to the prediction and interpretation of experimental outcomes. The results showcase the performance of the GiBUU-based simulation framework, emphasizing its fidelity to the original GiBUU cross-section model. This first implementation enables future work on developing the infrastructure to propagate systematic uncertainties. These contributions enhance the precision of experimental predictions and provide a platform for further exploration in future studies.

    ↳ hep-exhep-phComput.Phys.Commun.(2025)·5 citations
32. 32*

    Universal characterization of Efimovian $D^{0}nn$ System via Faddeev Techniques

    Ghanashyam Meher🇮🇳 · Sourav Mondal🇮🇳 · Udit Raha🇮🇳

    We demonstrate remnant structural universality in a putative S-wave $2n$-halo-bound $D^{0}nn$ system in the $J=0,T=3/2$ channel by invoking the zero-coupling limit (ZCL), which eliminates sub-threshold decay channels. Within this framework, we evaluate the one- and two-body matter density form factors, their associated root mean-square radii, and the $n$-$D^0$-$n$ opening angle. Our analysis is carried out at leading order using a quantum mechanical Faddeev technique in the momentum representation. Employing Jacobi momenta, we construct a complete partial-wave basis to expand the full three-body $D^{0}nn$ wave function across distinct rearrangement channels. Projection onto this basis yields a coupled set of Faddeev integral equations that govern the multiple-scattering dynamics of the constituent coupled spin-isospin subsystems. By introducing short-range separable interactions and expressing the two-body scattering amplitudes via spectator functions, we establish a direct correspondence with the familiar Skornyakov-Ter-Martirosyan equations from halo-EFT approach at leading order. A regulator-dependent analysis highlights the Efimov-like character of the three-body observables, with ground state properties exhibiting marked sensitivity to cutoff variations. However, the inclusion of a three-body force suppresses this dependence, as expected from renormalization-group invariance. We thereby conclude that, for sufficiently shallow three-body binding, the $D^{0}nn$ system in the ZCL exhibits a universal halo-bound structure. The subtle implications of range-like corrections at LO are addressed at a qualitative level in this analysis.

    ↳ nucl-thhep-phNPA(2026)·1 citation
33. 33*

    Fourier Calculus from Intersection Theory

    Giacomo Brunello🇮🇹 · Giulio Crisanti🇮🇹 · Mathieu Giroux🇨🇦 · Pierpaolo Mastrolia🇮🇹 · Sid Smith🇮🇹

    Building on recent advances in studying the co-homological properties of Feynman integrals, we apply intersection theory to the computation of Fourier integrals. We discuss applications pertinent to gravitational bremsstrahlung and deep inelastic scattering in the saturation regime. After identifying the bases of master integrals, the latter are evaluated by means of the differential equation method. Finally, new results with exact dependence on the spacetime dimension D are presented.

    ↳ hep-thhep-phPRD(2024)·27 citations
34. 34*

    Constraining axionlike particles with invisible neutrino decay using the IceCube observations of NGC 1068

    Bhanu Prakash Pant🇮🇳

    In the beyond Standard Model (BSM) scenarios, the possibility of neutrinos decaying into a lighter state is one of the prime quests for the new-generation neutrino experiments. The observation of high-energy astrophysical neutrinos by IceCube opens up a new avenue for studying neutrino decay. In this work, we investigate a novel scenario of invisible neutrino decay to axionlike particles (ALPs). These ALPs propagate unattenuated and reconvert into gamma rays in the magnetic field of the Milky Way. This is complementary and independent of the previously done studies where gamma rays produced at the source are used to investigate the ALP hypothesis. We exploit the Fermi-LAT and IceCube observations of NGC 1068 to set constraints on the ALP parameters. Being a steady source of neutrinos, it offers a better prospect over transient sources. We obtain 95% confidence level (CL) upper limits on the photon-ALP coupling constant $g_{a\gamma }\lesssim 1.37\times 10^{-11}$ GeV${}^{-1}$ for ALP masses $m_a\le 2\times 10^{-9}$ eV. Our results are comparable to previous upper limits obtained using the GeV to sub-PeV gamma-ray observations. Moreover, we estimate the contribution from NGC 1068-like sources to diffuse gamma-ray flux at GeV energies under the ALP scenario.

    ↳ astro-ph.HEastro-ph.COhep-phPRD(2024)·7 citations
35. 35*

    Strong Constraints on Dark Matter Annihilation in Ursa Major III/UNIONS 1

    Milena Crnogorčević🇸🇪 · Tim Linden🇸🇪

    Very recent work has identified a new satellite galaxy, Ursa Major III/UNIONS I, which is the faintest such system ever observed. Dynamical considerations indicate that if the system is in equilibrium, it is likely to be highly dark matter dominated. This, in combination with its proximity, predicts that it may be the preeminent dwarf spheroidal galaxy target for dark matter indirect detection searches. We utilize 15 years of Fermi-LAT data to search for $\gamma$-ray emission from Ursa Major III. Finding no excess, we set strong constraints on dark matter annihilation. Intriguingly, if the high J-factor of Ursa Major III is confirmed, standard thermal dark matter annihilation to $b\bar{b}$ final states would be ruled out for dark matter masses up to 4 TeV. The discovery of Ursa Major III, combined with recent tentative measurements of other high J-factor systems, suggests the exciting possibility that near-future data could produce transformative constraints on thermal dark matter.

    ↳ astro-ph.HEastro-ph.GAhep-phPRD(2024)·23 citations
36. 36*

    Master Formulae for $N$-photon tree level amplitudes in plane wave backgrounds

    Patrick Copinger🇬🇧 · James P. Edwards🇬🇧 · Anton Ilderton🇬🇧 · Karthik Rajeev🇬🇧

    The presence of strong electromagnetic fields adds huge complexity to QED Feynman diagrams, such that new methods are required to calculate higher-loop and higher-multiplicity scattering amplitudes. Here we use the worldline formalism to present `Master Formulae' for all tree level amplitudes of two massive particles and an arbitrary number of photons, in a plane wave background, in both scalar and spinor QED. The plane wave is treated without approximation throughout, meaning in particular that our formulae are valid in the strong-field regime of current theoretical and experimental interest. We check our results against literature expressions obtainable at low multiplicity via direct Feynman diagram calculations.

    ↳ hep-thhep-phPRD(2024)·16 citations
37. 37*

    Lattice investigations of the chimera baryon spectrum in the Sp(4) gauge theory

    Ed Bennett🇬🇧 · Deog Ki Hong🇰🇷 · Ho Hsiao🇹🇼 · Jong-Wan Lee🇰🇷 · C.-J. David Lin🇹🇼 · Biagio Lucini🇬🇧 · Maurizio Piai🇬🇧 · Davide Vadacchino🇬🇧

    We report the results of lattice numerical studies of the Sp(4) gauge theory coupled to fermions (hyperquarks) transforming in the fundamental and two-index antisymmetric representations of the gauge group. This strongly-coupled theory is the minimal candidate for the ultraviolet completion of composite Higgs models that facilitate the mechanism of partial compositeness for generating the top-quark mass. We measure the spectrum of the low-lying, half-integer spin, bound states composed of two fundamental and one antisymmetric hyperquarks, dubbed chimera baryons, in the quenched approximation. In this first systematic, non-perturbative study, we focus on the three lightest parity-even chimera-baryon states, in analogy with QCD, denoted as ${\Lambda }_{\mathrm{CB}}$, ${\Sigma }_{\mathrm{CB}}$ (both with spin 1/2), and ${\Sigma }_{\mathrm{CB}}^{\ast }$(with spin 3/2). The spin-1/2 such states are candidates of the top partners. The extrapolation of our results to the continuum and massless-hyperquark limit is performed using formulae inspired by QCD heavy-baryon Wilson chiral perturbation theory. Within the range of hyperquark masses in our simulations, we find that ${\Sigma }_{\mathrm{CB}}$ is not heavier than ${\Lambda }_{\mathrm{CB}}$.

    ↳ hep-lathep-phhep-thPRD(2024)·29 citations
38. 38*

    Landau Singularities Revisited: Computational Algebraic Geometry for Feynman Integrals

    Claudia Fevola🇫🇷 · Sebastian Mizera🇺🇸 · Simon Telen🇩🇪

    We reformulate the analysis of singularities of Feynman integrals in a way that can be practically applied to perturbative computations in the Standard Model in dimensional regularization. After highlighting issues in the textbook treatment of Landau singularities, we develop an algorithm for classifying and computing them using techniques from computational algebraic geometry. We introduce an algebraic variety called the principal Landau determinant, which captures the singularities even in the presence of massless particles or UV/IR divergences. We illustrate this for 114 example diagrams, including a cutting-edge 2-loop 5-point non-planar QCD process with multiple mass scales. The algorithms introduced in this work are implemented in the open-source Julia package PLD.jl available at https://mathrepo.mis.mpg.de/PLD/.

    ↳ hep-thhep-phPRL(2024)·73 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.